The instant invention relates generally to a hydrogen based ecosystem made possible by revolutionary new hydrogen storage alloys that are able, for the first time to realistically use the most ubiquitous, ultimate source of fuel for the next millennium and beyond, hydrogen. More particularly, there is described the use of such hydrogen storage alloys integrated with a system that combines all the necessary attributes to solve not only the safe and efficient storage problem, but also the infrastructure problem. It enables transportation and delivery of hydrogen for, by way of example and not limitation, powering internal combustion engine or fuel cell vehicles. Generally the system is a hydrogen production/distribution system in which waste heat generated in any subsystem thereof is recovered and reused in other subsystems. This system is the most efficient manner of transporting and delivering hydrogen.
The instant patent application for the first. time, describes a complete generation/storage/transportation/delivery system for a hydrogen-based economy. This is made possible by hydrogen storage alloys that have surmounted the chemical, physical, electronic and catalytic barriers that have heretofore been considered insoluble. These alloys are fully described in copending U.S. patent application Ser. No. 09/435,497, entitled xe2x80x9cHIGH STORAGE CAPACITY ALLOYS ENABLING A HYDROGEN-BASED ECOSYSTEMxe2x80x9d, filed Nov. 5, 1999 for Ovshinsky et al. (xe2x80x9cthe ""497 applicationxe2x80x9d). The ""497 application relates generally and specifically to alloys which solve the, up to now, unanswered problem of having sufficient hydrogen storage capacity with exceptionally fast kinetics to permit the safe and efficient storage of hydrogen to provide fuel for a hydrogen based economy, such as powering internal combustion engine and fuel cell vehicles. The instant invention in combination with the ""497 application solves the twin basic barriers which have held back the use of the xe2x80x9cultimate fuel,xe2x80x9d namely hydrogen storage capacity and a hydrogen infrastructure. The infrastructure is here solved since there is now an acceptable storage material. With the use of such alloy, hydrogen can be shipped safely by boats, barges, trains, trucks, etc. when in solid form. The complete infrastructure system from xe2x80x9csource to wheelxe2x80x9d is the subject of the instant application. Such an infrastructure requires thermal management and efficient heat utilization throughout the entire system, and that is what has been accomplished herein.
In the ""497 application the inventors for the first time disclosed the production of Mg-based alloys having both hydrogen storage capacities higher than about 6 wt. % and extraordinary kinetics. This revolutionary breakthrough was made possible by considering the materials as a system and thereby utilizing chemical modifiers and the principles of disorder and local order, pioneered by Stanford R. Ovshinsky (one of the instant inventors), in such a way as to provide the necessary catalytic local order environments, such as surfaces and at the same time designing bulk characteristics for storage and high rate charge/discharge cycling. In other words, these principles allowed for tailoring of the material by controlling the particle and grain size, topology, surface states, catalytic activity, microstructure, and total interactive environments for storage capacity.
As the world""s population expands and its economy increases, the atmospheric concentrations of carbon dioxide are warming the earth causing climate change. However, the global energy system is moving steadily away from the carbon-rich fuels whose combustion produces the harmful gas. Experts say atmospheric levels of carbon dioxide may be double that of the pre-industrial era by the end of the next century, but they also say the levels would be much higher except for a trend toward lower-carbon fuels that has been going on for more than 100 years. Furthermore, fossil fuels cause pollution and are a causative factor in the strategic military struggles between nations. Furthermore, fluctuating energy costs are a source of economic instability worldwide
For nearly a century and a half, fuels with high amounts of carbon have progressively been replaced by those containing less. First wood, which is high in carbon, was eclipsed in the late 19th century by coal, which contains less carbon. Then oil, with a lower carbon content still, dethroned xe2x80x9cKing Coalxe2x80x9d in the 1960""s. Now analysts say that natural gas, lighter still in carbon, may be entering its heyday, and that the day of hydrogenxe2x80x94providing a fuel with no carbon at allxe2x80x94may at last be about to dawn. As a result, experts estimate the world""s economy today bums less than two-thirds as much carbon per unit of energy produced as it did in 1860, despite the fact that carbon based duels are still being used by the automotive industry.
In the United States, it is estimated, that the trend toward lower-carbon fuels combined with greater energy efficiency has, since 1950, reduced by about half the amount of carbon spewed out for each unit of economic production. Thus, the decarbonization of the energy system is the single most important fact to emerge from the last 20 years of analysis of the system. It had been predicted that this evolution will produce a carbon-free energy system by the end of the 21st century. The present invention shortens that period to a matter of years. In the near term, hydrogen will be used in fuel cells for cars, trucks and industrial plants, just as it already provides power for orbiting spacecraft. But ultimately, hydrogen will also provide a general carbon-free fuel to cover all fuel needs.
As noted in recent newspaper articles, large industries, especially in America, have long been suspicious of claims that the globe is warming and have vociferously negated the science of climate change. Electric utilities, among others, initially took the position that international treaties on climate change would cut economic growth and cost jobs. A dramatic shift has now occurred, in which the problems are acknowledged and efforts are now being made to solve them. Therefore, it is very encouraging that some of the world""s biggest companies, such as Royal Dutch/Shell and BP Amoco, two large European oil firms, now state plainly what was once considered heresy: global warming is real and merits immediate action. A number of American utilities vow to find ways to reduce the harm done to the atmosphere by their power plants. DuPont, the world""s biggest chemicals firm, even declared that it would voluntarily reduce its emissions of greenhouse gases to 35% of their level in 1990 within a decade. The automotive industry, which is a substantial contributor to emissions of greenhouse gases and other. pollutants (despite its vehicular specific reductions in emissions), has now realized that change is necessary as evidenced by their electric and hybrid vehicles. In this field, the assignee of the subject invention, has developed the Ovonic nickel metal hydride battery, the enabling battery making electric and hybrid vehicles possible.
FIG. 1, taken from reliable industrial sources, is a graph demonstrating society""s move toward a carbon-free environment as a function of time starting with the use of wood in the early 1800s and ending in about 2010 with the beginning of a xe2x80x9chydrogenxe2x80x9d economy. In the 1800s, fuel was primarily wood in which the ratio of hydrogen to carbon was about 0.1. As society switched to the use of coal and oil, the ratio of hydrogen to carbon increased first to 1.3 and then to 2. Currently, society is inching closer to the use of methane in which the hydrogen to carbon ratio is further increased to 4 (methane has serious problems with safety, cost and infrastructure). However, the ultimate goal for society is to employ a carbon-free fuel, i.e., the most ubiquitous of elements, pure hydrogen. The obstacle has been the lack of solid state storage capacity and infrastructure. The inventors of the subject patent application and the ""497 application have made this possible by inventing a 7% storage material (7% is an umoptimized fugure and will be increased along with better kinetics) with exceptional absorption/desorption kinetics, i.e. at least 80% charge in less than 2 minutes. These alloys allow for the first time, a safe, high capacity means of storing, transporting and delivering pure hydrogen, which is the subject of the instant application.
Hydrogen is the xe2x80x9cultimate fuel.xe2x80x9d In fact, it is considered by most to be xe2x80x9cTHExe2x80x9d fuel for the next millennium, and, it is inexhaustible. Hydrogen is the most plentiful element in the universe (over 95%) and was the first element created by the xe2x80x9cBig-Bang.xe2x80x9d Hydrogen can provide an inexhaustible, clean source of energy for our planet which can be produced by various processes which split water into hydrogen and oxygen. The hydrogen can be stored and transported in solid state form. The instant patent application describes a complete generation/storage/transportation/delivery system for such a hydrogen based economy. For example, economical, lightweight, triple-junction amorphous silicon solar cells solar cells (an invention pioneered by Stanford R. Ovshinsky, one of the instant inventors) such as those set forth in U.S. Pat. No. 4,678,679, (the disclosure of which is herein incorporated by reference) can be readily disposed adjacent a body of water, where their inherently high open circuit voltage can be used to dissociate water into its constituent gases, and collect the hydrogen so produced. Also, by placing these high efficiency, lightweight solar panels on nearby farms, in water, or on land. Also, the photovoltaic process for dissociating water to form hydrogen can be a step toward solving the problems of water purification throughout the world. Electricity can be generated to transport and pump the hydrogen into metal hydride storage beds that include the high storage capacity, lightweight metal hydride alloys. The ultra-high capacities of the alloys of the ""497 application allow this hydrogen to be stored in solid form and transported by barge, tanker, train or truck in safe, economical form for ultimate use. Energy is the basic necessity of life and civilization for any society today and the use of hydrogen in the manner described herein as the basic source of energy would minimize the likelihood fought for control of fossil fuels. Instead of xe2x80x9cfrom well to wheel,xe2x80x9d the phrase now recited will be xe2x80x9cfrom source to wheel.xe2x80x9d
In the past considerable attention has been given to the use of hydrogen as a fuel or fuel supplement. While the world""s oil reserves are depletable, the supply of hydrogen remains virtually unlimited. Hydrogen can be produced from coal, natural gas and other hydrocarbons, or formed by the electrolysis of water, preferably via energy from the sun which is composed mainly of hydrogen and can, itself, be thought of as a giant hydrogen xe2x80x9cfurnacexe2x80x9d. Moreover hydrogen can be produced without the use of fossil fuels, such as by the electrolysis of water using nuclear or solar energy, or any other form of economical energy (e.g., wind, waves, geothermal, etc.). Furthermore, hydrogen, is an inherently low cost fuel. Hydrogen has the highest density of energy per unit weight of any chemical fuel and is essentially non-polluting since the main by-product of xe2x80x9cburningxe2x80x9d hydrogen is water. Thus, hydrogen can be a means of solving many of the world""s energy related problems, such as climate change, pollution, strategic dependancy on oil, etc., as well as providing a means of helping developing nations.
While hydrogen has wide potential application as a fuel, a major drawback in its utilization, especially in mobile uses such as the powering of vehicles, has been the lack of an acceptable lightweight hydrogen storage medium. Storage of hydrogen as a compressed gas involves the use of large and heavy vessels. Thus, as shown in FIG. 2, compressed hydrogen at 5000 psi only has a hydrogen density of 31 g/liter. Additionally, large and very expensive compressors are required to store hydrogen as a compressed gas and compressed hydrogen gas is a very great explosion/fire hazzard.
Hydrogen also can be stored as a liquid. Storage as a liquid, however, presents a serious safety problem when used as a fuel for motor vehicles since hydrogen is extremely flammable. Liquid hydrogen also must be kept extremely cold, below xe2x88x92253xc2x0 C., and is highly volatile if spilled. Moreover, liquid hydrogen is expensive to produce and the energy necessary for the liquefaction process is a major fraction of the energy that can be generated by burning the hydrogen. Another drawback to storage as a liquid is the costly losses of hydrogen due to evaporation, which can be as high as 5% per day. Also, the storage density of liquid hydrogen, as shown in FIG. 2 is only 71 g/liter.
For the first time, storage of hydrogen as a solid hydride, using the atomically engineered alloys of the instant application can provide a greater percent weight storage than storage as a compressed gas or a liquid in pressure tanks. Also, hydrogen storage in a solid hydride is safe and does not present any of the safety problems that hydrogen stored in containers as a gas or a liquid does because hydrogen, when stored in a solid hydride form, exists in it""s lowest free energy state. As shown, again in FIG. 2, storage of hydrogen in a 7% Ovonic thermal hydrogen storage alloy provides a hydrogen density of 103 g/liter, more than 3 times the density of compressed hydrogen gas.
In addition to the problems associated with storage of gaseous or liquid hydrogen, there are also problems associated with the transport of hydrogen in such forms. For instance transport of liquid hydrogen will require super-insulated tanks, which will be heavy and bulky and will be susceptible to rupturing and explosion. Also, a portion of the liquid hydrogen will be required to remain in the tanks at all times to avoid heating-up and cooling down of the tank which would incur big thermal losses. As for gaseous hydrogen transportation, pressurized tankers could be used for smaller quantities of hydrogen, but these too will be susceptible to rupturing and explosion. For larger quantities, a whole new hydrogen pipeline transportation system would need to be constructed or the compressor stations, valves and gaskets of the existing pipeline systems for natural gas will have to be adapted and retrofitted to hydrogen use, and this is assuming the construction material of these existing pipelines will be suited to hydrogen transportation.
Thus, there remains a compelling and crucial a need in the art for a complete infrastructure system for the generation/storage/transportation/delivery of hydrogen which overcomes the limitations of the prior art.
The instant invention provides a complete infrastructure system for the generation/storage/transportation/delivery of hydrogen which in turn makes a hydrogen ecosystem possible. This infrastructure system must be highly energy efficient, and such is achieved utilizing high capacity, low cost, light weight Ovonic thermal hydrogen storage alloy materials having fast kinetics. Generally the system is a hydrogen production/distribution system in which waste heat generated in any subsystem thereof is recovered and reused in other subsystems. Thus, the thermal energy budget for the entire system is optimized for the most efficient use of heat energy. The system includes the following subsystems: 1) power generation; 2) hydrogen generation; 3) hydrogen purification/compression; 4) hydrogen storage in hydride bed; 5) hydride bed transportation via truck, train, boat, barge, etc.; 6) a hydrogen distribution network; and 7) hydrogen end use. Throughout this infrastructure heat of hydride formation is recovered for reuse, such as for releasing hydrogen from a source hydride bed or for hydrogen/power generation.
The hydrogen is stored in a magnesium based hydrogen storage alloy powder. These alloys, for the first time make it feasible to use solid state storage and delivery of hydrogen to power a hydrogen based economy, and particularly to power mobile energy consumer applications such as internal combustion engine or fuel cell vehicles. The alloy contains greater than about 90 weight % magnesium and has a) a hydrogen storage capacity of at least 6 weight %; b) absorption kinetics such that the alloy powder absorbs 80% of it""s total capacity within 5 minutes at 300xc2x0 C.; c) a particle size range of between 30 and 70 microns, and d) a proper microstructure. More preferably the alloy powder has a hydrogen storage capacity of at least 6.5 weight % and most preferably at least 6.9 weight %. Also, the alloy powder more preferably absorbs 80% of it""s total capacity within 2 minutes at 300xc2x0 C. and most preferably within 1.5 minutes. Modifiers elements added to the magnesium to produce the alloys mainly include Ni and Mm (misch metal) and can also include additional elements such as Al, Y and Si. Thus the alloys will typically contain 0.5-2.5 weight % nickel and about 1.0-4.0 weight % Mm (predominantly contains Ce and La and Pr). The alloy may also contain one or more of 3-7 weight % Al, 0.1-1.5 weight % Y and 0.3-1.5 weight % silicon. Also, optionally, a small amount (up to 1%) of light elements such as carbon and/or boron, may be added to the alloy to increase the number of catalytically active sites therein.
The instant invention also provides a novel hydride storage bed design for the storage of hydrogen in a hydrogen storage alloy. The bed includes a unique support/heat-transfer component, which is made from a highly porous, high thermal conductivity, solid material. The preferred material is a high thermal conductivity graphitic foam.
The instant invention further provides a material including at least one particle having atomically engineered local chemical and electronic environments, characterized in that the local environments providing bulk nucleation.